Photodetection device and method for manufacturing photodetection device

Abstract

A method of manufacturing a photodetection device, the method includes preparing a light-receiving element including a first main surface including an arrangement of a plurality of first electrodes, forming a first bump containing In on each of the plurality of first electrodes, preparing a circuit substrate including a second main surface including an arrangement of a plurality of second electrodes, forming a second bump containing In on each of the plurality of second electrodes, forming, at at least one of a surface of the first bump or a surface of the second bump, a first oxide film containing In, placing the first main surface and the second main surface so as to face each other, and placing the first bump and the second bump on top of each other with the first oxide film therebetween.

What is claimed is: 
     
         1 . A method of manufacturing a photodetection device, the method comprising:
 preparing a light-receiving element including a first main surface including an arrangement of a plurality of first electrodes;   forming a first bump containing indium on each of the plurality of first electrodes;   preparing a circuit substrate including a second main surface including an arrangement of a plurality of second electrodes;   forming a second bump containing indium on each of the plurality of second electrodes;   forming a first oxide film containing indium on at least one of a surface of the first bump or a surface of the second bump;   aligning the first bump and the second bump on top of each other with the first oxide film therebetween by placing the first main surface and the second main surface so as to face each other; and   bonding together the first bump and the second bump to form a conductive connection portion under reduction of the first oxide film by heat treating in a reducing atmosphere.   
     
     
         2 . The method of manufacturing a photodetection device according to  claim 1 , wherein the first oxide film is formed at least on the surface of the first bump. 
     
     
         3 . The method of manufacturing a photodetection device according to  claim 1 , wherein the first oxide film is formed on both of the surface of the first bump and the surface of the second bump. 
     
     
         4 . The method of manufacturing a photodetection device according to  claim 1 , wherein the first oxide film has a thickness of 1 nm or more. 
     
     
         5 . The method of manufacturing a photodetection device according to  claim 1 , wherein the first oxide film is formed by sputtering, vacuum evaporation, thermal oxidation, natural oxidation, or wet treatment. 
     
     
         6 . The method of manufacturing a photodetection device according to  claim 1 , wherein the reducing atmosphere includes formic acid. 
     
     
         7 . The method of manufacturing a photodetection device according to  claim 1 , the method further comprising forming, at a surface of the conductive connection portion, a second oxide film containing In. 
     
     
         8 . The method of manufacturing a photodetection device according to  claim 7 , wherein the second oxide film has a thickness of 1 nm or more. 
     
     
         9 . A photodetection device comprising:
 a light-receiving element including a first main surface including an arrangement of a plurality of first electrodes;   a circuit substrate including a second main surface facing the first main surface and including an arrangement of a plurality of second electrodes;   a plurality of conductive connection portions containing indium and connecting each of the first electrodes to a corresponding one of the second electrodes; and   a plurality of oxide films formed individually at surfaces of the plurality of conductive connection portions and containing indium.